Player 1 is located on the left. Opponent/player 2 on right. Up/down to move player 2. W/S to move player 1. If you don't like the default physics, you can edit them in the settings menu.
This game plays in a very similar way to pong, but with a side-on view of the court, giving the ball gravity. Inspired by PONG (1972) and Tennis For Two (1958).